I think the egg incubation thing has gone slightly off-topic (though it's an interesting topic in and of itself). To the OP: you've been given good information already by members of this site about what's going on with your BPs.

You love your pets, and so I think you'll be willing to do what needs to be done to keep them safe and healthy. A pre-mature breeding on your younger female (if you have one of each sex) could injure or kill her. If the sexes are reversed and the larger snake is a female and you do get a clutch of eggs, are you prepared to care for several new hatchlings months from now? Do you have space to keep them all separately when they hatch or were you planning to also house any possible babies with their parents (also not a good idea)? If you don't have the space, do you have a plan to find them all new homes with responsible keepers?

If you've been seeing locks between them, and more than just the dominating behavior, then you could be facing the questions above. I, like many others here, would suggest separating them.